The present inventions are related to systems and methods for data processing, and more particularly to systems and methods for detecting patterns in a data stream.
Various circuits have been developed that provide for identifying synchronization marks within a data stream. Identifying a sync mark in a data stream is a critical step in block/frame synchronization in a read channel. The block/frame synchronization is usually achieved by writing a special sequence of bits called sync mark at the beginning of the sector. When detected correctly the sync mark denotes the beginning of the data. The sync mark may be detected, for example, by a Euclidean detector circuit that calculates a Euclidean distance between the sequence of received samples equalized to particular target and ideal samples corresponding to the binary sync mark and given target. This distance is compared to a static threshold, and a sync mark found is declared when the distance is smaller than the static threshold. Such a static threshold comparison approach depends highly upon determining an appropriate threshold for comparison. Where the selected threshold is too high, sync marks will be missed. Alternatively, where the selected threshold is too low, sync marks may be incorrectly identified. Either case is problematic for proper data processing.
Hence, for at least the aforementioned reasons, there exists a need in the art for advanced systems and methods for sync mark identification.